Based in developmental psychopathology paradigms of risk, resilience and prevention, this study seeks to extend 9 annual assessments of a cohort of about 300 affluent students (New England Study of Suburban Youth, NESSY; DA014385). Students have been followed from the 6th-12th grades at school and post freshman year at college, and we are now conducting assessments post sophomore year of college. The NESSY study has involved multiple measures, constructs, and respondents, with retention of 85-90% over time. Results thus far have shown substantial elevations in many adjustment problems especially substance use and rule-breaking among both girls and boys, and elevated depression and anxiety among the girls. PUBLIC HEALTH RELEVANCE PARAGRAPH: In the proposed study, we seek to follow this cohort for 4 additional annual assessments post Years 3 and 4 of college, and the first 2 years after college graduation, toward pursuing the following Specific Aims: (1) To examine developmental trajectories of substance use through early adulthood; (2) To examine antecedents of early adult substance use, considering a) prior parent and peer socializing dimensions, b) mediators of links between socializing dimensions and substance use (i.e., youths' overemphasis on achievements, internalizing and externalizing problems), and c) potential moderators involving youths' personal characteristics; (3) To examine the consequence of substance use for early adulthood including a) psychological problems, b) academic performance, and c) quality of close relationships as rated by others. Recent studies of other affluent teen samples corroborate our findings with NESSY youth, showing high substance use and related problems relative to norms. The long-term ramifications of these adolescent disturbances, however, are presently unknown. This study would be the first to yield multi-wave data on a cohort of affluent youth, illuminating trajectories (and/or potential maturing out) of substance use and associated problems across adolescence and early adulthood (spanning the high-risk college years as well as the transition out of college, potentially into jobs and committed long-term relationships). With multi- informant data gathered from middle childhood onwards and high retention, prospective analyses of risk and protective processes could be invaluable in informing interventions for youth such as these -- a non-trivial proportion of whom have consistently reported high levels of substance use over several years.